[0001] This invention relates to a gravity actuated, moveable mounting. In particular, the
invention relates to such a mounting suitable for attachment to an apparatus that
is periodically inverted, or at least tilted from one orientation to another. An example
of such an apparatus is a reversible plough, on which it is desirable to present e.g.
a depth sensor in an operative position regardless of which way up the plough is in
use.
[0002] In GB-A-2.105.966 a reversible plough is shown having a gauge wheel which pivots
from one extreme position to another extreme position under influence of its own weight,
upon turning the plough body form one operative position to another. Means are provided
to control the load on the tractor in response to the load applied to the gauge wheel.
However, no depth sensors are provided to measure the depth of the plough shares.
[0003] It's an object of the present invention to provide a reversible plough having only
a single sensor for measuring the depth of the plough, irrespective of the operative
position of the plough body.
[0004] According to the invention, there is provided a reversible plough including a gravity-actuated,
moveable mounting comprising :
- a shaft rotatably secured on the mounting;
- a mass secured to the shaft in a position radially spaced from its axis of rotation;
and
- a retainer retaining an invertible article, secured to the shaft for rotation therewith,
the arrangement being such that the action of gravity on the mass causes the retainer
to occupy a first predetermined position relative to the mounting and on partial or
complete inversion of the mounting to occupy a second position relative thereto.
[0005] The plough is characterized in that :
- the invertible article is a plough depth sensor of the type capable of generating
signals indicative of the distance of the lower end of the sensor from e.g. the ground;
and
- the mounting further comprises means for indicating the position of the mounting.
[0006] The mounting advantageously permits the depth sensor always to be presented at the
same orientation relative to the plough, regardless of the position of the plough.
The mounting of the invention is cheap and simple to manufacture, and obviates the
need e.g. for respective depth sensors associated with each position of use of the
plough.
[0007] Preferably the mounting includes a biasing member for biasing the retainer towards
its first or second position, depending on the position of the mounting. In preferred
embodiments, the biasing member includes an elastic member acting between a rotatable
part of the mounting and a point fixed relative to the mounting. In a particularly
preferred embodiment, the biasing member operates in an "over centre" action, whereby
to bias the mounting towards its first or second position only when gravity acts on
the mass to bias the mounting toward the respective first or second position.
[0008] These features advantageously provide an action for the mounting that is positive.
The use of a biasing member to bias the mounting to its first or second position means
that e.g. oscillations of the article to which the mounting is secured have a minimal
effect on the position of the mounting in use.
[0009] Preferably the biasing member is pivotably secured at the point fixed relative to
the mounting; and optionally also pivotably secured to the rotatable part of the mounting.
These features facilitate the "over centre" action of the mounting.
[0010] Conveniently the mounting includes a mounting arm for the mass, the biasing member
acting between the said arm and a point fixed relative to the journal.
[0011] The use of a mounting advantageously spaces the mass from the axis of rotation of
the rotatable part, and provides a convenient attachment point for one end of e.g.
a resilient member such as a spring serving as the biasing member.
[0012] In preferred embodiments the indicator of the position of the mounting includes one
or more transducers for generating electrical signals indicative of the position of
the mounting.
[0013] Conveniently, the mounting includes a pair of microswitches operable by a moveable
part of the mounting to generate electrical signals indicative of the mounting occupying
its first and second positions respectively.
[0014] Preferably the mounting includes a frame fixedly supporting the journal, and the
microswitches conveniently are secured at respective, spaced locations on the frame
for engagement by the moveable part of the mounting when the mounting occupies its
respective first and second positions.
[0015] These features confer an advantageously compact configuration on the mounting of
the invention.
[0016] Preferably the frame includes guides for the moveable part of the mounting that operates
the or each transducer. In one embodiment of the invention, the transducers are configured
as microswitches disposed at the ends of the guides along which the moveable part
of the mounting travels. This configuration is compact and reliable in operation.
[0017] Preferably the moveable part is constituted as the mounting arm for the mass. Alternatively,
another moveable part of the mounting may be thus employed. For example, the retainer
referred to hereinabove may equally readily be engageable with the transducer(s) on
operation of the mounting.
[0018] According to a further aspect of the invention there is provided a method of calibrating
a depth sensor of a reversible implement such as the reversible plough (7) mounted
on a vehicle (5), the depth sensor (17) being secured on the implement (7) via a mounting
(10) according to any of the Claims 1 to 14; and
the method comprising the steps of:
(I) raising a first side of the vehicle to a height equivalent to a depth d1 of operation of the implement when in use in a first orientation;
(ii) placing a surface at a first distance from the sensor equivalent to the distance
measured by the sensor during operation of the implement at said depth d1 in said first orientation;
(iii) causing the distance sensor to emit a first signal;
(iv) recording the first signal as a calibration value associated with said first
depth d1 and said first orientation of the implement;
(v) lowering the first side of the vehicle;
(vi) inverting the implement to occupy a second orientation;
(vii) raising the other side of the vehicle to a height equivalent to a depth d2 of operation of the implement when in use in said second orientation;
(viii) placing a surface at a second distance from the sensor equivalent to a further
distance measured by the sensor during operation of the implement at said depth d2 in said second orientation;
(ix) causing the distance sensor to emit a second signal;
(xi) recording the second signal as a calibration signal associated with the second
depth d2 and the second orientation of the implement.
[0019] There now follows a description of a preferred embodiment of the invention, by way
of example, with reference being made to the accompanying drawings in which:
Figure 1 shows an apparatus in accordance with the invention secured to a reversible
plough;
Figure 2 shows part of the Figure 1 arrangement, viewed from the other side of the
plough, in greater detail; and
Figure 3 shows a method of calibrating a plough depth sensor mounted via an apparatus
according to the invention.
[0020] Referring to the drawings and in particular Figure 1, there is shown the rear part
of a tractor 5 having a conventional three point hitch 6, two of the limbs 6a, 6b
of which are visible. A reversible, fully mounted plough 7 is secured to the hitch
6 by means of an intermediate frame 8. The upper and lower shares of the plough 7
are indicated by reference numerals 7a and 7b.
[0021] A mounting 10 in accordance with the invention for an ultrasound depth sensor 17
is shown secured to the central member 9 of plough 7, towards the forwardmost end
thereof. This location of mounting 10 is convenient since it allows operation of mounting
10 (in a manner described below) and depth sensor 17 (in a
per se known manner) without any risk of soil clogging the sensor 17. However, other locations
for mounting 10 are possible.
[0022] Referring to Figure 2, mounting 10 includes a rotatable, generally cylindrical shaft
11 supported in cantilever fashion protruding from an annular journal bearing 12.
A mass in the form of metal disc 13 is secured to shaft 11 at a position spaced radially
from the pivot axis of shaft 11 by virtue of mounting arm 14. In the orientation of
the mounting shown in Figure 2 the upper end of mounting arm 14 is secured to shaft
11 by welding. Metal disc 13 is secured to arm 14 by means of conventional screws
15a and 15b.
[0023] The free end 11a of shaft 11 has welded thereto a retainer in the form of a radial
arm 16 terminating in a 90° crank 16a at its end remote from shaft 11. Crank 16a includes
a through-going aperture for retention therein of an invertible article that is intended
to be secured in the mounting. In the embodiment shown, the invertible article is
an ultrasonic depth sensor 17, the emitter/receiver of which faces downwardly.
[0024] Depth sensor 17, which is
a per se known item, has a threaded, cylindrical body that is retained in the through-going
aperture in crank 16a by virtue of lock nuts 18a, 18b threaded onto the body of depth
sensor 17 to clamp about crank 16a. Of course, various other retention means, such
as clamps, adhesive pads and magnets may be employed in replacement of or in addition
to the aperture and locknut arrangement described for retaining the invertible article.
[0025] A conventional cable 19 extends from the upper end of depth sensor 17, for transmission
of electrical signals indicative of the distance of the lower end of sensor 17 from
e.g. the ground.
[0026] Cable 19 is connected e.g. to a suitable processor, that may be incorporated into
a CAN (controller area network) for controlling the functions of the apparatus to
which the mounting 10 is secured.
[0027] Journal 12 is secured to a generally U-shaped frame member 21, so that shaft 11 protruding
from journal 12 extends generally parallel to the arms of the U. When the mounting
is oriented as shown in Figure 1, the arms of the U lie horizontal one above the other.
The arms include respective guides in the form of notches 22a, 22b that are aligned
with one another and with the locus of mounting arm 14, whose motion is described
below.
[0028] Respective microswitches 23a and 23b are secured to the arms of the U of the frame
member 21 adjacent the notches 22a, 22b for engagement by the mounting arm 14 in a
manner to be described below.
[0029] A threaded rod 24 extends perpendicular to mounting arm 14 and has pivotably secured
at its free end 24a a biasing member in the form of elastic tensile spring 26. The
opposite end of tensile spring 26 is pivotably secured to the exterior of frame member
21. Thus, one end of spring 26 is as a result pivotably secured to a location fixed
relative to the number 10.
[0030] Frame member 21 includes a mounting plate 27 having apertures for securing of the
mounting 10 via screws to an apparatus intended to tilt or invert in use.
[0031] In the example shown, the apparatus to which the mounting 10 is secured is a reversible
plough. Some components of the plough, such as a plough width adjusting actuator 28,
are visible in Figure 2.
[0032] As is well known, the shares of a plough are set at an angle to the direction of
motion of a tractor towing the plough. Since the tractor (and hence the plough) reverses
its direction of travel at the end of each pass along a field when ploughing, the
plough has to be inverted at the end of each pass (usually as the tractor turns in
the headland) in order to ensure that the furrows created by the plough all face in
the same direction. The plough may include suitable powered actuators such as hydraulic
cylinders that permit inversion of the plough as required.
[0033] It is frequently desirable for the tractor operator (or a microprocessor monitoring
the operation of the plough) to receive information on the depth to which ploughing
occurs. It is therefore known to secure a depth sensor such as the sensor 17 of Figure
2 to the plough for measuring the distance between a datum point on the plough and
the surface of the soil being tilled.
[0034] Hitherto, on so called reversible ploughs (i.e. those ploughs that are capable of
inversion as described hereinabove) it has been known to provide two depth sensors.
One depth sensor operates when the plough occupies its first orientation, and the
other when the plough is inverted.
[0035] It will be appreciated that the mounting of the invention obviates the need for two
depth sensors. This is because on inversion of the plough shown in Figure 1, gravity
acts on the mass 13 as the plough turns, in order to cause pivoting of shaft 11 in
journal 12. This causes retainer 16 to rotate about the pivot axis of shaft 11, thereby
inverting depth sensor 17 substantially simultaneously with the plough.
[0036] Spring 26 tends to bias the mounting 10 towards one or other of its operative positions.
Thus the mounting 10 does not invert until the plough has itself turned over by more
than a predetermined minimum angular distance sufficient for the gravity force acting
on mass 13 to overcome the biasing force of spring 26. Once this angular inversion
of the plough has been attained, on continued rotation of the plough the mounting
10 moves rapidly towards its alternative position, by virtue of the "over centre"
action caused by spring 26.
[0037] As is clear from Figure 2, the pivotable mounting of the ends of spring 26 facilitates
this action.
[0038] As the arm 14 supporting disc 13 approaches each of its operative positions, it engages
and is guided by one of the notches 22a or 22b (as appropriate). This causes arm 14
to engage and actuate one or other (as appropriate) of the microswitches 23a, 23b.
This in turn sends an electrical signal via appropriate cabling 29 indicative of the
orientation of the plough. Since the mean height of the plough relative to e.g. the
tractor towing it varies as between the two possible positions of the plough, the
use of the microswitches (or other transducers) obviates the need for repeated recalibration
of the depth sensor each time the plough inverts. On the contrary, the microswitches
advantageously minimise the number of calibrations to two (i.e. one for each orientation
of the plough).
[0039] Calibration of the depth sensor is necessary for several reasons, including the following
:
- The emitter of depth sensor 17 is unlikely in practice to be level with the axis about
which the plough 7 rotates when inverting. Thus the emitter will be at different heights
relative to the surface of the soil depending on which way up the plough is orientated.
- And since the tractor has one wheel in the furrow when ploughing, the depth sensor
17 does not extend vertically downwardly, with the result that the distance between
the emitter of the sensor 17 and the surface of the soil is not the same as it would
be if the tractor stood on level ground.
[0040] Referring now to Figure 3, there follows a description of a method according to the
invention for calibrating the depth sensor 17 of a plough 7 having a mounting 10 according
to the invention.
[0041] Figure 3 is a rear view of tractor 5 showing intermediate frame 8 and mounting 10,
but omitting the remainder of plough 7 which would otherwise obscure mounting 10.
[0042] In the calibration method of the invention one rear wheel (in Figure 3 the left hand
rear wheel 31) of tractor 5 is raised onto a block 32 of predetermined height d equivalent
to the depth of a typical furrow that the shares of plough 7 are set to plough. This
gives tractor 5 the lateral inclination shown in Figure 3, which simulates the orientation
of tractor 5 when ploughing such a furrow.
[0043] Raising of wheel 31 may be achieved by jacking tractor 5 or, more preferably, by
driving wheel 31 onto a ramp incorporated into block 32.
[0044] A similar block to block 32 visible in Figure 3 may be used to raise the left hand
front wheel of tractor 5, fully to simulate the tilting of the tractor during ploughing
operations.
[0045] Once tractor 5 has been tilted as described, a further block 33 of height d is placed
on the ground beneath sensor 17. Block 33 simulates the surface of soil to one side
of a ploughed furrow, shown schematically by dotted lines in Figure 3.
[0046] With block 33 in place, the distance x
1 between the emitter of sensor 17 and the upper surface of block 33, is measured.
This distance x
1 may be stored in a processor (on board tractor 5 for processing output signals from
sensor 17) and used during real time operation of sensor 17 during ploughing to the
aforesaid depth as a calibration value for sensor signals encoded to indicate the
orientation of plough 7 at the time of recording the distance x
1. Such encoding is achieved through the settings of microswitches 23 during the calibration
procedure shown in Figure 3.
[0047] Block 33 is then removed and wheel 31 lowered to ground level. Plough 7 is inverted,
which causes mounting 10 to invert in the manner described above. This in turn causes
the configuration of the microswitches 23 to invert, encoding signals from sensor
17 in a different way than previously. The calibration method is then repeated, but
on this occasion right hand rear wheel 35 (and if necessary the right hand front wheel)
of tractor 5 is raised on a block 32 to simulate the effect of the tractor facing
in the opposite direction with its wheels on the left hand side in the furrow. Measurement
of the distance x
2 from the sensor emitter to block 33 gives a further calibration value, for use when
the mounting 10 occupies its second position.
[0048] It will be appreciated that the calibration process described results in the storing
of two calibration values of distance x. However, ploughs generally are such that
the ploughing depth is adjustable. Thus it would be desirable to repeat the calibration
procedure for at least one (and preferably more than one) further value of height
d, from which a calibration curve may be interpolated that may be used to provide
calibration values for a range of ploughing depths. The calibration curve may be stored,
for example, as a look-up table in the memory of the processor previously mentioned.
Clearly under such circumstances it would be necessary to employ a series of sets
of blocks 32, 33 of different heights d.
[0049] Thus the mounting of the invention advantageously permits consistent depth measurements
to be taken using a reversible plough.
1. A reversible plough (7) including a gravity-actuated, moveable mounting (10) comprising
:
- a shaft (11) rotatably secured on the mounting (10);
- a mass (13) secured to the shaft (11) in a position radially spaced from its axis
of rotation; and
- a retainer (16) retaining an invertible article, secured to the shaft (11) for rotation
therewith, the arrangement being such that the action of gravity on the mass (13)
causes the retainer (16) to occupy a first predetermined position relative to the
mounting (10) and on partial or complete inversion of the mounting (10) to occupy
a second position relative thereto; and
characterized in that :
- the invertible article is a plough depth sensor (17) of the type capable of generating
signals indicative of the distance of the lower end of the sensor from e.g. the ground;
and
- the mounting (10) further comprises means (23a, 23b) for indicating the position
of the mounting (10).
2. A plough according to Claim 1 characterized in that the mounting (10) further includes a biasing member (24, 26) for biasing the retainer
(16) towards its first or second position, depending on the position of the mounting
(10).
3. A plough according to Claim 2 characterized in that the biasing member (24, 26) includes an elastic member (26) acting between a rotatable
part (14) of the mounting (10) and a point (21) fixed relative to the mounting (10).
4. A plough according to Claim 2 or Claim 3 characterized in that the biasing member (24, 26) operates in an "over centre" action, whereby to bias
the retainer (16) towards its first or second position only when gravity acts on the
mass (13) to bias the mounting (10) towards the respective first or second position.
5. A plough according to Claim 4 characterized in that the biasing member (24, 26) is pivotably secured at the point fixed relative to the
mounting (10), whereby to facilitate its "over centre" action.
6. A plough according to Claim 4 or Claim 5 characterized in that the biasing member (24, 26) is pivotably secured to said rotatable part of the mounting
(10).
7. A plough according to any of Claims 2 to 6 characterized in that the mounting (10) further includes a mounting arm (14) for the mass (13), the biasing
member (24, 26) acting between the said arm (14) and a point fixed relative to the
mounting (10).
8. A plough according to any of the preceding claims characterized in that the means (23a, 23b) for indicating the position of the mounting (10) includes one
or more transducers (23a, 23b) for generating electrical signals indicative of the
position of the mounting (10).
9. A plough according to Claim 8 characterized in that the mounting (10) further includes a pair of microswitches (23a, 23b) operable by
a moveable part (14) of the mounting (10) to generate electrical signals indicative
of the mounting (10) occupying first and second positions respectively.
10. A plough according to any of the preceding claims characterized in that the shaft (11) is rotatably secured in a journal (12), the mounting (10) including
a frame (21) fixedly supporting the journal (12).
11. A plough according to Claim 10 when dependent from Claim 9 characterized in that the microswitches (23a, 23b) are secured at respective, spaced locations on the frame
(21) for engagement by said moveable part (14) of the mounting (10) when the mounting
(10) occupies its respective first and second positions.
12. A plough according to Claim 10 or Claim 11, characterized in that the frame (21) includes guides (22a, 22b) for the moveable part (14) of the mounting
(10) that operates the or each transducer (23a, 23b).
13. A plough according to any of the Claims 9 to 12 when dependent from Claim 7, characterized in that the moveable part is constituted as the mounting arm (14) for the mass (13).
14. A plough according to any of the preceding claims characterized in that the plough depth sensor (17) is secured in the retainer (16) of the mounting (10).
15. A method of calibrating the depth sensor (17) of a reversible implement such as the
reversible plough (7) mounted on a vehicle (5), the depth sensor (17) being secured
on the implement (7) via a mounting (10) according to any of the Claims 1 to 14; and
characterized in that the method comprises the steps of:
(i) raising a first side of the vehicle (5) to a height equivalent to a depth d1 of operation of the implement (7) when in use in a first orientation;
(ii) placing a surface at a first distance from the sensor (17) equivalent to the
distance measured by the sensor (17) during operation of the implement (7) at said
depth d1 in said first orientation;
(iii) causing the distance sensor (17) to emit a first signal;
(iv) recording the first signal as a calibration value associated with said first
depth d1 and said first orientation of the implement (7);
(v) lowering the first side of the vehicle (5);
(vi) inverting the implement (7) to occupy a second orientation;
(vii) raising the other side of the vehicle (5) to a height equivalent to a depth
d2 of operation of the implement (7) when in use in said second orientation;
(viii) placing a surface at a second distance from the sensor (17) equivalent to a
further distance measured by the sensor (17) during operation of the implement (7)
at said depth d2 in said second orientation;
(ix) causing the distance sensor (17) to emit a second signal;
(xi) recording the second signal as a calibration signal associated with the second
depth d2 and the second orientation of the implement (7).
16. A method according to Claim 15 characterized in that the steps (i) to (xi) are repeated for one or more further values of d1 and d2 corresponding to further depths of operation of the implement (7) in said first and
second orientations respectively.
1. Kehrpflug (7), der eine durch Schwerkraft betätigte bewegliche Aufhängung (10) einschließt,
mit:
- einer Welle (11), die drehbar auf der Aufhängung (10) befestigt ist;
- einer Masse (13), die an der Welle (11) in einer Position mit radialem Abstand von
deren Drehachse angeordnet ist; und
- einem Halter (16), der einen umkehrbaren Gegenstand hält, der an der Welle (11)
für eine Drehung mit dieser befestigt ist, wobei die Anordnung derart ist, daß die
Wirkung der Schwerkraft auf die Masse (13) bewirkt, daß der Halter (16) eine erste
vorgegebene Position bezüglich der Aufhängung (10) einnimmt, und bei einer teilweisen
oder vollständigen Umkehrung der Aufhängung (10) eine zweite Position relativ hierzu
einnimmt;
dadurch gekennzeichnet, daß:
- der umkehrbare Gegenstand ein Pflugtiefen-Sensor (17) von der Art ist, die in der
Lage ist, Signale zu erzeugen, die die Entfernung des unteren Endes des Sensors von
beispielsweise dem Boden anzeigen; und
- die Aufhängung (10) weiterhin Einrichtungen (23a, 23b) zur Anzeige der Position
der Aufhängung (10) umfaßt.
2. Pflug nach Anspruch 1, dadurch gekennzeichnet, daß die Aufhängung (10) weiterhin ein Vorspannelement (24, 25) zur Vorspannung des Halters
(16) in Richtung auf seine erste oder zweite Stellung in Abhängigkeit von der Position
der Aufhängung (10) einschließt.
3. Pflug nach Anspruch 2, dadurch gekennzeichnet, daß das Vorspannelement (24, 26) ein elastisches Element (26) einschließt, das zwischen
einem drehbaren Teil (14) der Aufhängung (10) und einem Punkt (21) wirkt, der bezüglich
der Aufhängung (10) festgelegt ist.
4. Pflug nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß das Vorspannelement (24, 26) in einer "Sprungwerk"-Wirkung arbeitet, wodurch der
Halter (16) in Richtung auf seine erste oder zweite Position nur dann vorgespannt
wird, wenn die Schwerkraft auf die Masse (13) wirkt, um die Aufhängung (10) in die
jeweilige erste oder zweite Position vorzuspannen.
5. Pflug nach Anspruch 4, dadurch gekennzeichnet, daß das Vorspannelement (24, 26) schwenkbar an dem gegenüber der Aufhängung (10) festgelegten
Punkt befestigt ist, um auf diese Weise seine "Sprungwerk"-Wirkung zu erleichtem.
6. Pflug nach Anspruch 4 oder 5, dadurch gekennzeichnet, daß das Vorspannelement (24, 26) schwenkbar an dem drehbaren Teil der Aufhängung (10)
befestigt ist.
7. Pflug nach einem der Ansprüche 2 bis 6, dadurch gekennzeichnet, daß die Aufhängung (10) weiterhin einen Befestigungsarm (14) für die Masse (13) einschließt,
wobei das Vorspannelement (24, 26) zwischen dem Arm (14) und einem gegenüber der Aufhängung
(10) festgelegten Punkt wirkt.
8. Pflug nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Einrichtung (23a, 23b) zur Anzeige der Position der Aufhängung (10) einen oder
mehrere Wandler (23a, 23b) zur Erzeugung elektrischer Signale einschließt, die die
Position der Aufhängung (10) anzeigen.
9. Pflug nach Anspruch 8, dadurch gekennzeichnet, daß die Aufhängung (10) weiterhin ein Paar von Mikroschaltern (23a, 23b) einschließt,
die durch einen beweglichen Teil (14) der Aufhängung (10) betätigbar sind, um elektrische
Signale zu erzeugen, die die Einnahme der ersten bzw. zweiten Position durch die Aufhängung
(10) anzeigen.
10. Pflug nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Welle (11) drehbar in einem Drehlager (12) gelagert ist, wobei die Aufhängung
(10) weiterhin einen Rahmen (21) einschließt, der das Drehlager (12) starr haltert.
11. Pflug nach Anspruch 10, unter Rückbeziehung auf Anspruch 9, dadurch gekennzeichnet, daß die Mikroschalter (23a, 23b) an jeweiligen mit Abstand angeordneten Positionen auf
dem Rahmen (21) für einen Eingriff mit dem beweglichen Teil (14) der Aufhängung (10)
befestigt sind, wenn die Aufhängung (10) ihre jeweiligen ersten und zweiten Positionen
einnimmt.
12. Pflug nach Anspruch 10 oder 11, dadurch gekennzeichnet, daß der Rahmen (21) Führungen (22a, 22b) für den beweglichen Teil (14) der Aufhängung
(10) einschließt, der den oder jeden Wandler (23a, 23b) betätigt.
13. Pflug nach einem der Ansprüche 9 bis 12 unter Rückbeziehung auf Anspruch 7, dadurch gekennzeichnet, daß der bewegliche Teil als der Befestigungsarm (14) für die Masse (13) gebildet ist.
14. Pflug nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß der Pflugtiefen-Sensor (17) in dem Halter (16) der Aufhängung (10) befestigt ist.
15. Verfahren zum Eichen des Tiefensensors (17) eines umkehrbaren Anbaugeräts, wie zum
Beispiel eines Kehrpflugs (7), das bzw. der auf einem Fahrzeug (5) befestigt ist,
wobei der Tiefensensor (17) an dem Anbaugerät (7) über eine Aufhängung (10) gemäß
einem der Ansprüche 1 bis 14 befestigt ist;
dadurch gekennzeichnet, daß das Verfahren die folgenden Schritte umfaßt:
(i) Anheben einer ersten Seite des Fahrzeugs (5) auf eine Höhe, die einer Betriebstiefe
d1 des Anbaugeräts (7) äquivalent ist, wenn dieses in einer ersten Ausrichtung im Betrieb
ist;
(ii) Anordnen einer Oberfläche an einer ersten Entfernung von dem Sensor (17), die
äquivalent zu der Entfernung ist, die von dem Sensor (17) während des Betriebs des
Anbaugeräts (7) in der Tiefe d1 bei der ersten Ausrichtung gemessen wird;
(iii) Bewirken, daß der Entfernungssensor (17) ein erstes Signal aussendet;
(iv) Aufzeichnen des ersten Signals als einen Eichwert, der der ersten Tiefe d1 und der ersten Ausrichtung des Anbaugeräts (7) zugeordnet ist,
(v) Absenken der ersten Seite des Fahrzeugs (5);
(vi) Umkehren des Anbaugeräts (7) derart, daß dieses eine zweite Ausrichtung einnimmt;
(vii) Anheben der anderen Seite des Fahrzeugs (5) auf eine Höhe, die einer Betriebstiefe
d2 des Anbaugeräts (7) äquivalent ist, wenn diese in der zweiten Ausrichtung im Gebrauch
ist;
(viii) Anordnen einer Oberfläche in einer zweiten Entfernung von dem Sensor (17),
die äquivalent zu einer weiteren Entfernung ist, die von dem Sensor (17) während des
Betriebs des Anbaugeräts (7) in der Tiefe d2 bei der zweiten Ausrichtung gemessen wird;
(ix) Bewirken, daß der Entfemungssensor (17) ein zweites Signal aussendet;
(xi) Aufzeichnen des zweiten Signals als ein Eichsignal, das der zweiten Tiefe d2 und der zweiten Ausrichtung des Anbaugeräts (7) zugeordnet ist.
16. Verfahren nach Anspruch 15, dadurch gekennzeichnet, daß die Schritte (i) bis (xi) für einen oder mehrere Werte von d1 und d2 entsprechend weiteren Betriebstiefen des Anbaugeräts (7) in den ersten bzw. zweiten
Ausrichtungen wiederholt werden.
1. Charrue réversible (7) comprenant un montage mobile (10) actionné par gravité et comportant:
- un arbre (11) fixé rotativement sur le montage (10) ;
- une masse (13) fixée sur l'arbre (11) dans une position radialement écartée de son
axe de rotation; et
- un organe de retenue (16), retenant un composant réversible, fixé sur l'arbre (11)
en rotation par rapport à ce dernier, l'arrangement étant tel que l'action de la gravité
sur la masse (13) entraîne l'organe de retenue (16) à occuper une première position
prédéterminée par rapport au montage (10) et, lors d'un retournement partiel ou complet
du montage (10), à occuper une seconde position par rapport à ce dernier.
La charrue est
caractérisée en ce que :
- le composant réversible est un détecteur de profondeur de charrue (17) du type capable
de générer des signaux indicateurs de la distance entre l'extrémité inférieure du
capteur et par exemple le sol; et
- le montage (10) comprend en outre des moyens (23a; 23b) destinés à indiquer la position
du montage (10).
2. Charrue selon la revendication 1, caractérisée en ce que le montage (10) comprend en outre un organe de contrainte (24, 26) destiné à contraindre
l'organe de retenue (16) vers sa première ou seconde position, en fonction de la position
du montage (10).
3. Charrue selon la revendication 2, caractérisée en ce que l'organe de contrainte (24, 26) comprend un élément élastique (26) agissant entre
une pièce rotative (14) du montage (10) et un point (21) fixe par rapport au montage
(10).
4. Charrue selon la revendication 2 ou la revendication 3, caractérisée en ce que l'organe de contrainte (24, 26) fonctionne comme un "mouvement à détente brusque",
de manière à contraindre l'organe de retenue (16) vers sa première ou seconde position
uniquement lorsque la gravité agit sur la masse (13) afin de contraindre le montage
(10) respectivement vers la première ou la seconde position.
5. Charrue selon la revendication 4, caractérisée en ce que l'organe de contrainte (24, 26) est fixé avec pivotement au point fixe par rapport
au montage (10), de manière à faciliter son mouvement "à détente brusque".
6. Charrue selon la revendication 4 ou la revendication 5, caractérisée en ce que l'organe de contrainte (24, 26) est fixé avec pivotement à ladite pièce rotative
du montage (10).
7. Charrue selon l'une quelconque des revendications 2 à 6, caractérisée en ce que le montage (10) comprend en outre un bras de montage (14) pour la masse (13), l'organe
de contrainte (24, 26) agissant entre ledit bras (14) et un point fixe par rapport
au montage (10).
8. Charrue selon l'une quelconque des revendications précédentes, caractérisée en ce que les moyens (23a, 23b) d'indication de la position du montage (10) comprennent un
ou plusieurs transducteurs (23a, 23b) destinés à générer des signaux électriques indicateurs
de la position du montage (10).
9. Charrue selon la revendication 8, caractérisée en ce que le montage (10) comprend en outre une paire de microrupteurs (23a, 23b) pouvant être
actionnés par une pièce mobile (14) du montage (10) pour générer des signaux électriques
indicateurs des première et seconde positions respectives occupées par le montage
(10).
10. Charrue selon l'une quelconque des revendications précédentes, caractérisée en ce que l'arbre (11) est fixé rotativement dans un palier (12), le montage (10) comprenant
un châssis (21) soutenant fixement le palier (12).
11. Charrue selon la revendication 10 lorsqu'elle dépend de la revendication 9, caractérisée en ce que les microrupteurs (23a, 23b) sont fixés à des emplacements écartés respectifs sur
le châssis (21) afin d'être engagés par ladite pièce mobile (14) du montage (10) lorsque
le montage (10) occupe ses première et seconde positions respectives.
12. Charrue selon la revendication 10 ou la revendication 11, caractérisée en ce que le châssis (21) comprend des guides (22a, 22b) pour la pièce mobile (14) du montage
(10) qui actionne le ou chaque transducteur (23a, 23b).
13. Charrue selon l'une quelconque des revendications 9 à 12 lorsqu'elles dépendent de
la revendication 7, caractérisée en ce que la pièce mobile est constituée par le bras de montage (14) de la masse (13).
14. Charrue selon l'une quelconque des revendications précédentes, caractérisée en ce que le détecteur de profondeur (17) de la charrue est fixé dans l'organe de retenue (16)
du montage (10).
15. Méthode de calibrage d'un détecteur de profondeur (17) d'un outil réversible, tel
qu'une charrue réversible (7) montée sur un véhicule (5), le détecteur de profondeur
(17) étant fixé à l'outil (7) via un montage (10) selon l'une quelconque des revendications
1 à 14; et
la méthode comprenant les étapes:
(i) de soulèvement d'un premier côté du véhicule (5) à une hauteur équivalente à une
profondeur d1 de fonctionnement de l'outil (7) lorsqu'il est utilisé dans une première orientation;
(ii) de positionnement d'une surface à une première distance du détecteur (17) équivalente
à la distance mesurée par le détecteur (17) pendant le fonctionnement de l'outil (7)
à ladite profondeur d1 dans ladite première orientation;
(iii) de commandement du détecteur (17) de distance pour émettre un premier signal;
(iv) d'enregistrement du premier signal en tant que valeur de calibrage associée à
ladite première profondeur d1 et à ladite première orientation de l'outil (7);
(v) d'abaissement du premier côté du véhicule (5);
(vi) de retournement de l'outil (7) pour occuper une seconde orientation;
(vii) de soulèvement de l'autre côté du véhicule (5) à une hauteur équivalente à une
profondeur d2 de fonctionnement de l'outil (7) lorsqu'il est utilisé dans ladite seconde orientation;
(viii) de positionnement d'une surface à une seconde distance du détecteur (17) équivalente
à une autre distance mesurée par le détecteur (14) pendant le fonctionnement de l'outil
(7) à ladite profondeur d2 dans ladite seconde orientation;
(ix) de commandement du détecteur de distance (17) pour émettre un second signal;
(xi) d'enregistrement du second signal en tant que valeur de calibrage associée à
ladite seconde profondeur d2 et à ladite seconde orientation de l'outil (7).
16. Méthode selon la revendication 15, caractérisée en ce que les étapes (i) à (xi) sont répétées pour une ou plusieurs valeur(s) supplémentaire(s)
de d1 et d2 correspondant aux profondeurs supplémentaires de fonctionnement de l'outil (7) dans
lesdites première et seconde orientations respectives.